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Purpose: This paper draws attention to a welcome trend in certain areas of applied and experimental research that appears to endorse a General Systems Theory for the acquisition of knowledge., Method: By way of illustration it makes an appraisal of key studies of human/environmental interaction that were either derived from actual operational groups in naturalistic settings or contrived in the laboratory or the field to simulate extreme conditions., Results: It urges more anthropologists, physicians, physiologists, psychologists, and sociologists to follow suit and make their disciplinary boundaries permeable. Were they to do that, it is argued that their research methods would be more appropriate for studying the dynamic integration of their subject matter than those derived from the conventional use of scientific method., Conclusions: It asserts that the solutions to complex problems of human adaptation to the environment are not to be found within the domain of any single academic discipline.

This paper describes the results of a comparative screening between the nematophagous Antarctic fungus Arthrobotrys tortor and other species of that genus for the production of extracellular collagenases. The nematode species used in this study was Caenorhabditis elegans, feeding on Escherichia coli cultures. Determination of collagenase activity was made using insoluble collagen from bovine Achilles tendon and determining the amount of solubilized hydroxyproline produced. The results show that the total amount of collagenase produced by the Antarctic strain of A. tortor was about threefold higher than that observed for the other species. In the Antarctic strain, collagenase was shown to be a constitutive enzyme.

Psychrophilic and psycrotrophic organisms are important in global ecology as a large proportion of our planet is cold. Two-third of sea-water covering more than 70% of Earth is cold deep sea water with temperature around 2 degrees C, and more than 90% of freshwater is in polar ice-sheets and mountain glaciers. Though biological activity in snow and ice had been believed to be extremely limited, various specialized biotic communities were recently discovered at glaciers of various part of the world. The glacier is relatively simple and closed ecosystem with special biotic community containing various psychrophilic and psycrotrophic organisms. Since psychrophilic organisms was discovered in the deep ice-core recovered from the antarctic ice-sheet and a lake beneath it, snow and ice environments in Mars and Europa are attracting a great deal of scientific attention as possible extraterrestrial habitats of life. This paper briefly reviews the results of the studies on ecology of psychrophilic organisms living in snow and ice environments and their physiological and biochemical adaptation to low temperature.

In this paper we report the cloning and sequencing of two small plasmids, pTAUp and pTADw, from the Antarctic Gram-negative Psychrobacter sp strain TA144. The observation that pTAUp contains a putative Rep-coding gene (Psyrep) suggested that its duplication occurs via a rolling-circle replication mechanism. This hypothesis was confirmed by the identification of the pTAUp single-stranded DNA form. The putative pTAUp plus origin of replication was found at the 3' end of the Psyrep by using an in vivo complementation assay. Structural similarities at the level of (i) gene organization, (ii) protein sequence, and (iii) nick site sequences strongly suggest that the psychrophilic enzyme belongs to a new subfamily of replication enzymes., (Copyright 2000 Academic Press.)

Xylanase production by the Antarctic psychrophilic yeast Cryptococcus adeliae was increased 4.3 fold by optimizing the culture medium composition using statistical designs. The optimized medium containing 24.2 g l(-1) xylan and 10.2 g l(-1) yeast extract and having an initial pH of 7.5 yielded xylanase activity at 400 nkat (nanokatal) ml(-1) after 168-h shake culture at 4 degrees C. In addition, very little endoglucanase, beta-mannanase, beta-xylosidase, beta-glucosidase, alpha-L-arabinofuranosidase, and no filter paper cellulase activities were detected. Among 12 carbon sources tested, maximum xylanase activity was induced by xylan, followed by lignocelluloses such as steamed wheat straw and alkali-treated bagasse. The level of enzyme activity produced on other carbon sources appeared to be constitutive. Among the complex organic nitrogen sources tested, the xylanase activity was most enhanced by yeast extract, followed by soymeal, Pharmamedia (cotton seed protein), and Alburex (potato protein). A batch culture at 10 degrees C in a 5-1 fermenter (3.5-1 working volume) using the optimized medium gave 385 nkat at 111 h of cultivation. The crude xylanase showed optimal activity at pH 5.0-5.5 and good stability at pH 4-9 (21 h at 4 degrees C). Although the enzyme was maximally active at 45 degrees - 50 degrees C, it appeared very thermolabile, showing a half-life of 78 min at 35 degrees C. At 40 degrees - 50 degrees C, it lost 71%-95% activity within 5 min. This is the first report on the production as well as on the properties of thermolabile xylanase produced by an Antarctic yeast.

This paper describes 5 cases of injury to seabird researchers between 1996 and 1999 at Palmer Station, Antarctica. The injuries were inflicted by 3 seabird species: the Adelie penguin (Pygoscelis adeliae); the southern giant petrel (Macronectes giganteus); and the brown skua (Catharacta lonnbergi). All injured parties were biologic researchers with previous field experience working under National Science Foundation research grants; all sought medical evaluation and treatment voluntarily. The nature and frequency of such injuries seems not to have been greatly reported in the medical literature. Although these cases were largely soft tissue injuries that healed without serious complications, the possibility of exotic infections is considered. We have dubbed this constellation of injuries AVES (Antarctic Vogel [German for bird] Encounter Syndrome).

Panagrolaimus davidi is a freeze-tolerant Antarctic nematode which survives extensive intracellular freezing. This paper describes the development of culture techniques which provide clean samples, with a high degree of freeze tolerance and in sufficient quantities for the analysis of potential cryoprotectants. Cultures grown at 20 degrees C survived a short-term freezing stress but survival declined with the time spent frozen. Acclimation of cultures at 5 degrees C enhanced the long-term survival of freezing. Starvation, however, reduced the nematode's ability to survive short-term freezing. The principal cryoprotectants detected by gas chromatography were trehalose and glycerol. The levels of trehalose, but not those of glycerol, increased significantly after acclimation. Trehalose may stabilise membranes and protect them against the dehydrating effects of the osmotic stresses resulting from freeze concentration effects but other factors, such as recrystallisation inhibition, may be involved in long-term survival.

Anecdotal comparisons frequently are made between expeditions of the past and space missions of the future. Spacecraft are far more complex than sailing ships, but from a psychological perspective, the differences are few between confinement in a small wooden ship locked in the polar ice cap and confinement in a small high-technology ship hurtling through interplanetary space. This paper discusses some of the behavioral lessons that can be learned from previous expeditions and applied to facilitate human adjustment and performance during future space expeditions of long duration.

This paper evaluates whether 1) protoplatyrrhines could have migrated to South America via Antarctica, and 2) the floating island model is a plausible transoceanic mode of dispersal for land vertebrates like protoplatyrrhines. Results show that Eocene Antarctica and Australia supported large and dense forests, and that the Antarctic fauna was comprised of many species of vertebrates, including placental and marsupial land mammals. However, no primate remains have ever been reported from these continents. Antarctica and South America were connected until the Middle Eocene (i.e., after the oldest Asian anthropoids), but two major water barriers existed between Antarctica and Asia since the Early Eocene. The Eocene and Oligocene water gap separating Africa and Antarctica was excessively large. Thus, all scenarios involving an Antarctic route have been rejected. The African scenario is difficult to falsify because only one water barrier existed, both paleowinds and paleocurrents were favorable, and Paleogene African anthropoids show phylogenetic affinities to platyrrhines. I tested whether a journey on a hypothetical floating island over the Paleogene Atlantic Ocean exceeds the survival limit of a genetically viable group of animals such as protoplatyrrhines. Studies of water deprivation suggest that they could have been able, with a body weight averaging 1 kg, to survive without water for at least 13 days. I have used the present Atlantic Ocean as a model for the velocity of Paleogene paleowinds and paleocurrents. Considering winds as the key accelerating force of floating islands, the Paleogene Atlantic water barrier could have been crossed, in the most conservative scenario, in 8 days at 50 Mya, 11 days at 40 Mya, and 15 days at 30 Mya. In order to survive a transoceanic journey, however, protoplatyrrhines had to be preadapted to strong seasonal variations in water availability in their original (African) environment. Once on the sea, their brains would have physiologically interpreted the rarity of water as the beginning of the dry season, and the group would have switched its diet to alternative foods, i.e., everything available on the floating island., (Copyright 1999 Wiley-Liss, Inc.)

RD3, a new antifreeze protein (AFP) extracted from antarctic eel pout is a single polypeptide divided into homologous N-terminal (residues Asn(1)-Glu(64)) and C-terminal (residues Ser(74)-Glu(134)) domains, each of which has a high sequence identity with Type III AFP. A 9-residue linker (-D(65)GTTSPGLK(73)-) connects these two domains in tandem and is thought to play a significant role in defining the nature of the intact molecule. The present paper shows for the first time the solution structure and preliminary (15)N-NMR backbone dynamics data of the N-domain plus the linker of recombinant RD3 protein (RD3-Nl: residues 1-73) by employing homo- and heteronuclear multidimensional NMR spectroscopy. Forty converged structures of RD3-Nl were successfully calculated by using a total of 958 NMR-derived structural restraints. It was found that the N-domain of RD3-Nl has a globular form comprising six beta-strands, three type III turns, and several loops, which stabilize a flat, ice-binding site formed on one side of this domain. Further, the linker portion appears to have a definitive structure, which is independent of the globular N-domain. This definitive linker is roughly divided into two short strands, -D(65)GTTSP(70)- and -G(71)LK(73)-, which are bent around -T(67)TSPG(71)- at an angle of approximately 60 degrees. This bending motif of the linker may function to orient the two ice-binding sites of the N- and C-domains of RD3 in the same direction, leading to their simultaneous interactions with the ice crystal surface.

In the present paper, we examine eight species of Antarctic fish belonging to the suborder Notothenioidei, using reverse-transcriptase polymerase chain reaction, to investigate the presence of mRNAs encoding metallothionein (MT) isoforms. A total of 168 bp from the coding region and the complete (133-165 bp) 3' untranslated region (UTR) was obtained for all species (for three of them, we also sequenced the full-length cDNA, including the 5' UTR). Phylogenetic analyses carried out on the MT-coding region suggest monophyly for Antarctic fish MTs with respect to other teleost MT genes. Analyses also revealed that notothenioid MTs can be divided into at least two groups of paralogy, MT-1 and MT-2. These results indicate that notothenioid MT isoforms arose from at least one gene duplication event occurring in the ancestral lineage of the Notothenioidei. This duplication occurred independent of the one which gave origin to two metallothionein isoforms in the rainbow trout. In addition, an instance of gene conversion was observed between MT-1 and MT-2 genes in Notothenia coriiceps. Analyses of the 5' UTR, combined with quantitative assay of differential expression of MT-1 and MT-2, indicate that only the 3' UTR underwent a gene conversion event in the mentioned species. These findings, together with the observation of a differential pattern of expression for the two MT isoforms, disclose an unexpected complexity in the evolution and function of notothenioid MTs; as in most teleost species examined (apart from the rainbow trout), a single MT form is present.

Background: This paper reports a study which examined the impact of long-term isolation and confinement on multiple-task performance., Methods: A group of 10 scientists and 6 technicians from a French wintering-over expedition in the Antarctic participated in the 8-mo study. The group was tested 8 times on a computerized simulation of a complex life support system. The task environment allowed the measurement of primary and secondary task performance, system control activities and subjective operator state., Results: No signs of serious performance decrements were observed but a number of subtle indications of hidden decrements emerged. The data also revealed strong differences in performance between the professional groups. Finally, the paper discusses the implications of the work for extended spaceflight.

Analogous experience is often instructive when attempting to understand human behavior in extreme environments. The current paper refers to the experiences of polar explorers and remote duty personnel to help identify the factors that influence individual and team performance when small groups are isolated and confined for long durations. The principal factors discussed include organizational structure, intracrew communications, interpersonal relations, leadership style, personnel selection, and training. Behavioral implications also are addressed for the design of procedures and equipment to facilitate sustained individual and group performance under conditions of isolation and confinement. To be consistent with the theme of the symposium, this paper emphasizes the crew requirements for an international expedition to Mars.

The psychological effects of unusual environments reveal different aspects of behaviour from those seen in more customary situations. Such environments provide natural laboratories in which many questions of psychological interest, varying with the specific environment, may be studied. This paper uses isolated polar stations to illustrate this point. In such settings, the usual parameters that control a variety of psychological processes are drastically changed, and confounding variables are stripped away. Consequently, the environment offers unique perspectives on environmental perception and cognition; adaptation to and use of the environment; environmental bonding; social interaction; and coping with environmental challenge.

This paper reports Immunoglobulin M (IgM) levels in serum samples from eight female-pup pairs of southern elephant seals (Mirounga leonina), at King George Island, Antarctica. IgM levels were determined on sera obtained from sequential sampling throughout the suckling period (approximately 23 days). The IgM concentration in southern elephant seal serum was measured by single radial immunodiffusion on agarose plates. Female IgM levels (123.5-613.0 mg/dL, n = 8) were significantly higher than pup levels (5.9-123.6 mg/dL, n = 8). Both groups showed an increasing trend throughout the entire suckling period, with significant differences in relation to stages of lactation. Pup IgM levels on the first day of life (mean +/- SD, 7.6 +/- 2.9 mg/dL, n = 3) suggest that endogenous synthesis takes place before birth.

Until the 1950's, psychological adaptation to the polar regions was expressed by survivors more in terms of their endurance and heroism after the event than by any studied preparation beforehand, a careful monitoring of performance in situ, the follow-up of subjects afterwards, and a scholarly comparison of data-based research finding. This paper covers some of the omissions, and presents the results of a few studies that should be of value to the variety of people who for quite different periods and purposes visit polar regions. Because of the author's own background in Antarctic research it draws upon material collected in Antarctica, but it also includes empirical studies made by behavioural scientists in the Arctic. Its aim is to encourage potential venturers to the polar areas to prepare themselves mentally as well as physically and logistically for the task ahead of them, whether it be for the long winter night at base or for the long summer day in the field. It concludes with a plea for all the venturers to accept an obligation to provide research data on themselves. The outcome, if done systematically, could be of value both for future participants and for behavioural scientists, because in the past human factors in exploration have been given little attention.

The paper presents the results of studies of metabolic processes in the Arctic and Antarctic winters, members of Polar expeditions, and inhabitants of the Far North. There is a relationship between the metabolism and the length of residence in the area of low temperatures, lifestyle, and occupation. The experiments have shown changes in the phosphorylizing activity of rat hepatic mitochondria in the dynamics of cold adaptation in animals. In addition to the hormonal status and antioxidative system, serum lipoproteins were found to determine the response of the body to cold exposure. The regulatory role of the lipoprotein components apoproteins is discussed in the paper.

The paper presents the results of clinical, physiological and biochemical examination of 27 polar explorer--members of the 17th Soviet Antartic Expedition at the Vostok station. It gives data on the morbidity rate and describes the development of the asthenic-neurotic syndrome. On the basis of studies of catecholamines and serotonin, the role of the sympatho-adrenal system in the human adaptation to the harsh environments of the Central Antarctica has been shown.

In many aspects, an Antarctic Station provides parallels to the environments encountered in space exploration, particularly with reference to infectious disease. In both instances, small groups of people live in isolation for long periods of time in a functionally sterile atmosphere. Therefore, studies of infectious disease in Antarctica should provide important insights into the experiences to be expected in spaceflight. This paper presents a summary of the information on the infectious and immunologic aspects of isolation derived over the years from research in Antarctica.

The increasing prominence of polar, spaceflight, and subaquatic environments has renewed interest in understanding human performance under conditions of isolation and confinement. In 1987, the National Aeronautics and Space Administration and the National Science Foundation co-sponsored a conference intended to revitalize behavioral research in such settings, and to explore the use of Antarctica as a behavioral laboratory for outer space. The present paper reviews recent research on men and women in isolation and confinement, with special reference to the proceedings of the NASA/NSF conference. The literature reviewed, which focuses on living systems and cuts across the individual, small group, organization, and community levels, suggests that researchers have become more systems-oriented, and have broadened their perspectives to encompass missions' larger temporal and social contexts. Among the topics reviewed are states of consciousness, stress, health, small group dynamics, personnel selection, crew training, and environmental engineering. Methodological and logistical problems are discussed, and the review concludes with recommendations for agencies that sponsor groups in isolation and confinement and for researchers who seek to study such groups.

Faraday Base represents a small isolated community producing its own domestic water by desalination of sea water. During the Antarctic winter of 1986 (April to October), regular bacteriological examination of the water supply and surrounding sea took place. Samples were collected and examined every 2 weeks by the methods described in the Department of Health and Social Security Report No. 71, on the Bacteriological Examination of Drinking Water Supplies (DHSS, 1982), for membrane filtration and colony counting. The results of these examinations are presented in this paper. The results obtained suggest that water of good bacteriological quality was produced by the desalination plant, but some samples from the distribution system contained coliforms or presumptive Escherichia coli in small numbers. The possible reasons for this low-level contamination are discussed. No cases of gastroenteritis occurred on the base during this time.